is it possible to change currency on checkout?

Is it possible to change currency in the checkout page, based on these 2 conditions?
1. When user change their shipping address
2. When they change the currency using the floating widget?

I have tested this on my client’s website but I only managed to do either one.

If I turned on ‘Switch Currency by JS’ and change currency follow ‘Shipping Address’. But when i change the currency using the floating widget, the page keeps redirecting.